Cigarette smoking is a strong and common risk factor for alveolar bone loss and tooth loss as well as various other chronic diseases. Smoking is a complex exposure with several important characteristics that are difficult to account for in epidemiologic models of disease. The long-term objective of this project is to establish a comprehensive smoking index (CSI) that accounts for smoking intensity, duration and time since cessation in a single variable as a function of its biological effect on disease risk over time. [unreadable] [unreadable] Hypothesis: The CSI can both accurately and efficiently model smoking history in models of prevalent and incident alveolar bone loss and tooth loss and is an efficient and accurate tool to adjust for confounding by smoking in models on the relationship between periodontal disease and risk for cardiovascular diseases. Methods: This hypothesis will be tested using existing data from 1,231 subjects enrolled in the VA Dental Longitudinal Study (DLS), an established cohort of men with triennial comprehensive clinical and radiographic follow-ups over 30 years. Measures of radiographic alveolar bone loss, tooth loss, smoking history, clinical periodontal variables, medical status (including incident cardiovascular disease) and other [unreadable] covariates have been updated regularly over the follow-up period. In addition, tooth loss will be analyzed using existing data from 51,529 subjects in the Health-Professionals Follow-up Study (HPFS), an established cohort of men with biennial follow-up over 16 years. Cross-sectional and longitudinal analyses using regression models that adjust for known risk factors and potential confounders will be carried out. The novel CSI will be compared to various conventional approaches in models of alveolar bone loss and tooth loss, as well as in models on the association between periodontal bone loss and cardiovascular disease. Significance: The CSI may be an efficient way to capture different characteristics of smoking in a single variable to model smoking history in epidemiologic models of chronic disease. [unreadable] [unreadable] [unreadable] [unreadable]